The CPCRA Statistical Center will be responsible for providing statistical scientific leadership for all CPCRA research projects, from concept development through protocol implementation and subsequent amendment, including responsibility for data collection and quality assurance, statistical analysis, administrative reporting, and the education of CPCRA participants. Specific tasks will include the following: Establish and administer a reliable, efficient and responsive data management system with centralized data entry to reduce the burdensome aspects of conducting community-based research; - Recommend to the AIDS Program and other protocol team members the most appropriate experimental design for each CPCRA research study; - Design and distribute study forms for each CPCRA research study; - Design and implement quality assurance procedures to evaluate and improve the validity and completeness of computerized data; Perform all statistical analyses and administrative reporting required for CPCRA research projects; - Provide technical assistance and training to CPCRA participants, includin designing and implementing a series of workshops to educate community clinicians with respect to clinical research, protocol compliance, patient followup, and other statistical and data management issues and procedures.